This invention relates to a pressure regulating valve for crankcase ventilation in an internal combustion engine. Such pressure regulating valves for crankcase ventilation are disposed, for example, in the venting duct between the crankcase and the air intake filter or engine air intake manifold. Due to these pressure regulating valves there exists a continuous connection between the crankcase and the air intake side of the engine, through which the blow-by gases are sucked out and returned to the combustion process. The pressure regulating valve assures that the pressure in the crankcase will not fall below a specified level. A prevailing slight vacuum in the crankcase prevents the blow-by gas from escaping to the atmosphere. By regulating the crankcase pressure, an optimum sealing of the closed motor system is assured, so that no pollutants can escape into the atmosphere.
A pressure regulating valve is usually flange-mounted laterally on the motor and connected by appropriate ducts to the crankcase or air intake. Such valves are disclosed, for example, in publication No. VKD 7032 of Filterwerk Mann & Hummel GmbH.
On a motor, of course, a number of additional accessories are disposed, such as the distributor, oil filler tube, dip stick, fuel lines, injection valves, and the like. A disadvantage of this great number of additional devices is that they can make it difficult to inspect and service the engine.